Dopamine, Serotonin, Noradrenaline and Cortisol: What are they and how do they impact your dog’s emotions and behaviours.

Dopamine, Serotonin and Noradrenaline are neurotransmitters. Neurotransmitters play an integral role in the way signals are processed within the canine brain. They are chemicals which either increase or inhibit the signals which are transmitted across the synapses of one neuron to the other. Neurotransmitters all have their own roles and generate different responses in the dog’s brain. 

Dopamine:

This neural transmitter is associated with motivation and is known as the ‘feel good’ chemical. When a dog experiences this feel good chemical they are driven to repeat the behaviour/ action in order to benefit from this positive feeling. This is why positive canine coaching is effective as the dog gets an instant reward for their actions as well as the actual physical reward: play, rub, treat etc.

If a dog has excess dopamine they can be more impulsive, appear agitated or over-excited. Low levels on the other hand means the dog will be less motivated, under- reactive (not fussed) which can sometimes present as depression. 

Serotonin:

This neurotransmitter is directly linked to a dog’s mood, bonding behaviour, food selection, sexual behaviour and emotional state.

Serotonin has been identified as a calming neurotransmitter. This is why it has such a strong link with a dog's mood and emotional state. If this chemical is not balanced it can create drastic changes in the behaviours a dog presents with. If a dog is suffering from lowered levels they can have trouble regulating their emotions and behaviour; displaying heightened aggression, irritability and other negative behaviours such as lowered levels of inhibition.  

Noradrenaline: 

This is a key chemical to understand as it is linked to your dog's response to stress, threats and or danger. This chemical stimulates the dog’s ‘fight or flight’ response, stemming from their Sympathetic Nervous System. 

This chemical increases a dog’s alertness, vigilance and state of arousal. It affects their body by increasing their heart rate and blood sugar levels to provide energy to their muscles should they need to run or defend themselves. 

How does this affect their behaviour: This breaks down into two sections.

A dog who is exposed to continuous/excess exposure to noradrenaline will display heightened anxiety and have an escalated response to triggers. This is due to the fact their system already has an influx of this chemical and heightened arousal so another release of this chemical will increase and push their body past coping level. This is what we refer to as their ‘threshold’. This is the level of stress that a dog can deal with at one time. 

How does this affect their health?

When this chemical is released it suppresses their Parasympathetic Nervous System which is responsible for their rest and digest activity/cycles. Therefore, if you have an anxious or fearful dog their levels will sit higher for prolonged periods of time, which can lead to gastrointestinal issues and alter your dog's food preferences. This is why when a dog is very scared they refuse food, their body has suppressed that internal drive. They may also present as if they are depressed due to lack of energy caused by their stress.

Hormones:

There is a hormone called Cortisol which is released alongside noradrenaline. This hormone is the ‘stress’ hormone which ‘fight or flight’ responses in similar ways to noradrenaline: increase glucose and metabolism regulation. It is also responsible for immune responses. Dogs that have high levels of cortisol may suffer from suppressed immune systems, skin irritation and hair loss due to the excess of this hormone. 

How does this affect their mood?

This hormone can lead to more sensitive reactions to triggers. This is due to the fact that it takes time for it’s levels to deplete in a dog's system (up to 72 hrs); if the levels are extremely high they may not reset overnight after rest. So, a highly reactive/anxious/fearful dog who has been exposed to trigger after trigger, has surpassed their threshold will be displaying extreme behaviours (barking, lunging, snapping, shaking, hyperarousal) as their system is overloaded with noradrenaline and cortisol. This may take a couple of days to reduce all the way back to a base level; therefore if you go out the next day and exposure to triggers you are just topping up their stress levels and they will go over their threshold quicker. 

So, 

With these neurotransmitters in mind this is the science behind positive training and how we help our dog’s live a happy, well balanced life. Lot’s of dopamine, balanced serotonin and reduced cortisol. When we see our dog displaying negative behaviours, stop and think. Have they been stressed, what has happened today/yesterday?